format ExprListComp (#5600)

Co-authored-by: Micha Reiser <micha@reiser.io>

crates/ruff_python_formatter/resources/test/fixtures/ruff/statement/list_comp.py

@@ -0,0 +1,32 @@
+[i for i in []]
+
+[i for i in [1,]]
+
+[
+    a  # a
+    for # for
+    c  # c
+    in  # in
+    e  # e
+]
+
+[
+    # above a
+    a  # a
+    # above for
+    for # for
+    # above c
+    c  # c
+    # above in
+    in  # in
+    # above e
+    e  # e
+    # above if
+    if  # if
+    # above f
+    f  # f
+    # above if2
+    if  # if2
+    # above g
+    g  # g
+]

crates/ruff_python_formatter/src/comments/placement.rs

@@ -38,6 +38,7 @@ pub(super) fn place_comment<'a>(
         handle_slice_comments,
         handle_attribute_comment,
         handle_expr_if_comment,
+        handle_comprehension_comment,
         handle_trailing_expression_starred_star_end_of_line_comment,
     ];
     for handler in HANDLERS {
@@ -1244,6 +1245,137 @@ fn find_only_token_in_range(range: TextRange, locator: &Locator, token_kind: Tok
     token
 }
 
+// Handle comments inside comprehensions, e.g.
+//
+// ```python
+// [
+//      a
+//      for  # dangling on the comprehension
+//      b
+//      # dangling on the comprehension
+//      in  # dangling on comprehension.iter
+//      # leading on the iter
+//      c
+//      # dangling on comprehension.if.n
+//      if  # dangling on comprehension.if.n
+//      d
+// ]
+// ```
+fn handle_comprehension_comment<'a>(
+    comment: DecoratedComment<'a>,
+    locator: &Locator,
+) -> CommentPlacement<'a> {
+    let AnyNodeRef::Comprehension(comprehension) = comment.enclosing_node() else {
+        return CommentPlacement::Default(comment);
+    };
+    let is_own_line = comment.line_position().is_own_line();
+
+    // Comments between the `for` and target
+    // ```python
+    // [
+    //      a
+    //      for  # attache as dangling on the comprehension
+    //      b in c
+    //  ]
+    // ```
+    if comment.slice().end() < comprehension.target.range().start() {
+        return if is_own_line {
+            // own line comments are correctly assigned as leading the target
+            CommentPlacement::Default(comment)
+        } else {
+            // after the `for`
+            CommentPlacement::dangling(comment.enclosing_node(), comment)
+        };
+    }
+
+    let in_token = find_only_token_in_range(
+        TextRange::new(
+            comprehension.target.range().end(),
+            comprehension.iter.range().start(),
+        ),
+        locator,
+        TokenKind::In,
+    );
+
+    // Comments between the target and the `in`
+    // ```python
+    // [
+    //      a for b
+    //      # attach as dangling on the target
+    //      # (to be rendered as leading on the "in")
+    //      in c
+    //  ]
+    // ```
+    if comment.slice().start() < in_token.start() {
+        // attach as dangling comments on the target
+        // (to be rendered as leading on the "in")
+        return if is_own_line {
+            CommentPlacement::dangling(comment.enclosing_node(), comment)
+        } else {
+            // correctly trailing on the target
+            CommentPlacement::Default(comment)
+        };
+    }
+
+    // Comments between the `in` and the iter
+    // ```python
+    // [
+    //      a for b
+    //      in  #  attach as dangling on the iter
+    //      c
+    //  ]
+    // ```
+    if comment.slice().start() < comprehension.iter.range().start() {
+        return if is_own_line {
+            CommentPlacement::Default(comment)
+        } else {
+            // after the `in` but same line, turn into trailing on the `in` token
+            CommentPlacement::dangling((&comprehension.iter).into(), comment)
+        };
+    }
+
+    let mut last_end = comprehension.iter.range().end();
+
+    for if_node in &comprehension.ifs {
+        // ```python
+        // [
+        //     a
+        //     for
+        //     c
+        //     in
+        //     e
+        //     # above if   <-- find these own-line between previous and `if` token
+        //     if  # if     <-- find these end-of-line between `if` and if node (`f`)
+        //     # above f    <-- already correctly assigned as leading `f`
+        //     f  # f       <-- already correctly assigned as trailing `f`
+        //     # above if2
+        //     if  # if2
+        //     # above g
+        //     g  # g
+        // ]
+        // ```
+        let if_token = find_only_token_in_range(
+            TextRange::new(last_end, if_node.range().start()),
+            locator,
+            TokenKind::If,
+        );
+        if is_own_line {
+            if last_end < comment.slice().start() && comment.slice().start() < if_token.start() {
+                return CommentPlacement::dangling((if_node).into(), comment);
+            }
+        } else {
+            if if_token.start() < comment.slice().start()
+                && comment.slice().start() < if_node.range().start()
+            {
+                return CommentPlacement::dangling((if_node).into(), comment);
+            }
+        }
+        last_end = if_node.range().end();
+    }
+
+    CommentPlacement::Default(comment)
+}
+
 /// Returns `true` if `right` is `Some` and `left` and `right` are referentially equal.
 fn are_same_optional<'a, T>(left: AnyNodeRef, right: Option<T>) -> bool
 where

crates/ruff_python_formatter/src/expression/expr_list_comp.rs

@@ -1,20 +1,41 @@
 use crate::comments::Comments;
 use crate::expression::parentheses::{
-    default_expression_needs_parentheses, NeedsParentheses, Parentheses, Parenthesize,
+    default_expression_needs_parentheses, parenthesized, NeedsParentheses, Parentheses,
+    Parenthesize,
 };
-use crate::{not_yet_implemented_custom_text, FormatNodeRule, PyFormatter};
-use ruff_formatter::{write, Buffer, FormatResult};
+use crate::prelude::*;
+use crate::AsFormat;
+use crate::{FormatNodeRule, PyFormatter};
+use ruff_formatter::{format_args, write, Buffer, FormatResult};
 use rustpython_parser::ast::ExprListComp;
 
 #[derive(Default)]
 pub struct FormatExprListComp;
 
 impl FormatNodeRule<ExprListComp> for FormatExprListComp {
-    fn fmt_fields(&self, _item: &ExprListComp, f: &mut PyFormatter) -> FormatResult<()> {
+    fn fmt_fields(&self, item: &ExprListComp, f: &mut PyFormatter) -> FormatResult<()> {
+        let ExprListComp {
+            range: _,
+            elt,
+            generators,
+        } = item;
+
+        let joined = format_with(|f| {
+            f.join_with(soft_line_break_or_space())
+                .entries(generators.iter().formatted())
+                .finish()
+        });
+
         write!(
             f,
-            [not_yet_implemented_custom_text(
-                "[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]"
+            [parenthesized(
+                "[",
+                &format_args!(
+                    group(&elt.format()),
+                    soft_line_break_or_space(),
+                    group(&joined)
+                ),
+                "]"
             )]
         )
     }

crates/ruff_python_formatter/src/other/comprehension.rs

@@ -1,12 +1,87 @@
-use crate::{not_yet_implemented, FormatNodeRule, PyFormatter};
-use ruff_formatter::{write, Buffer, FormatResult};
-use rustpython_parser::ast::Comprehension;
+use crate::comments::{leading_comments, trailing_comments};
+use crate::prelude::*;
+use crate::AsFormat;
+use crate::{FormatNodeRule, PyFormatter};
+use ruff_formatter::{format_args, write, Buffer, FormatResult};
+use rustpython_parser::ast::{Comprehension, Ranged};
 
 #[derive(Default)]
 pub struct FormatComprehension;
 
 impl FormatNodeRule<Comprehension> for FormatComprehension {
     fn fmt_fields(&self, item: &Comprehension, f: &mut PyFormatter) -> FormatResult<()> {
-        write!(f, [not_yet_implemented(item)])
+        let Comprehension {
+            range: _,
+            target,
+            iter,
+            ifs,
+            is_async,
+        } = item;
+
+        let comments = f.context().comments().clone();
+
+        if *is_async {
+            write!(f, [text("async"), space()])?;
+        }
+
+        let dangling_item_comments = comments.dangling_comments(item);
+
+        let (before_target_comments, before_in_comments) = dangling_item_comments.split_at(
+            dangling_item_comments
+                .partition_point(|comment| comment.slice().end() < target.range().start()),
+        );
+
+        let trailing_in_comments = comments.dangling_comments(iter);
+        write!(
+            f,
+            [
+                text("for"),
+                trailing_comments(before_target_comments),
+                group(&format_args!(
+                    soft_line_break_or_space(),
+                    target.format(),
+                    soft_line_break_or_space(),
+                    leading_comments(before_in_comments),
+                    text("in"),
+                    trailing_comments(trailing_in_comments),
+                    soft_line_break_or_space(),
+                    iter.format(),
+                )),
+            ]
+        )?;
+        if !ifs.is_empty() {
+            let joined = format_with(|f| {
+                let mut joiner = f.join_with(soft_line_break_or_space());
+                for if_case in ifs {
+                    let dangling_if_comments = comments.dangling_comments(if_case);
+
+                    let (own_line_if_comments, end_of_line_if_comments) = dangling_if_comments
+                        .split_at(
+                            dangling_if_comments
+                                .partition_point(|comment| comment.line_position().is_own_line()),
+                        );
+                    joiner.entry(&group(&format_args!(
+                        leading_comments(own_line_if_comments),
+                        text("if"),
+                        trailing_comments(end_of_line_if_comments),
+                        soft_line_break_or_space(),
+                        if_case.format(),
+                    )));
+                }
+                joiner.finish()
+            });
+
+            write!(f, [soft_line_break_or_space(), group(&joined)])?;
+        }
+        Ok(())
+    }
+
+    fn fmt_dangling_comments(
+        &self,
+        _node: &Comprehension,
+        _f: &mut PyFormatter,
+    ) -> FormatResult<()> {
+        // dangling comments are formatted as part of fmt_fields
+        Ok(())
     }
 }

crates/ruff_python_formatter/tests/snapshots/black_compatibility@py_37__python37.py.snap

@@ -42,7 +42,7 @@ def make_arange(n):
 ```diff
 --- Black
 +++ Ruff
-@@ -2,29 +2,21 @@
+@@ -2,29 +2,27 @@
  
  
  def f():
@@ -60,13 +60,16 @@ def make_arange(n):
  
  async def func():
      if test:
--        out_batched = [
--            i
+         out_batched = [
+             i
 -            async for i in aitertools._async_map(
 -                self.async_inc, arange(8), batch_size=3
 -            )
--        ]
-+        out_batched = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
++            async for
++            i
++            in
++            aitertools._async_map(self.async_inc, arange(8), batch_size=3)
+         ]
  
  
  def awaited_generator_value(n):
@@ -95,7 +98,13 @@ def g():
 
 async def func():
     if test:
-        out_batched = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+        out_batched = [
+            i
+            async for
+            i
+            in
+            aitertools._async_map(self.async_inc, arange(8), batch_size=3)
+        ]
 
 
 def awaited_generator_value(n):

crates/ruff_python_formatter/tests/snapshots/black_compatibility@py_38__pep_572.py.snap

@@ -59,7 +59,7 @@ while x := f(x):
 ```diff
 --- Black
 +++ Ruff
-@@ -2,10 +2,10 @@
+@@ -2,7 +2,7 @@
  (a := a)
  if (match := pattern.search(data)) is None:
      pass
@@ -67,11 +67,7 @@ while x := f(x):
 +if (match := pattern.search(data)):
      pass
  [y := f(x), y**2, y**3]
--filtered_data = [y for x in data if (y := f(x)) is None]
-+filtered_data = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
- (y := f(x))
- y0 = (y1 := f(x))
- foo(x=(y := f(x)))
+ filtered_data = [y for x in data if (y := f(x)) is None]
 @@ -19,10 +19,10 @@
      pass
  
@@ -122,7 +118,7 @@ if (match := pattern.search(data)) is None:
 if (match := pattern.search(data)):
     pass
 [y := f(x), y**2, y**3]
-filtered_data = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+filtered_data = [y for x in data if (y := f(x)) is None]
 (y := f(x))
 y0 = (y1 := f(x))
 foo(x=(y := f(x)))

crates/ruff_python_formatter/tests/snapshots/black_compatibility@simple_cases__comments2.py.snap

@@ -224,36 +224,43 @@ instruction()#comment with bad spacing
      if (
          self._proc is not None
          # has the child process finished?
-@@ -114,25 +122,9 @@
-         # yup
+@@ -115,7 +123,12 @@
          arg3=True,
      )
--    lcomp = [
+     lcomp = [
 -        element for element in collection if element is not None  # yup  # yup  # right
--    ]
--    lcomp2 = [
--        # hello
--        element
--        # yup
--        for element in collection
--        # right
++        element  # yup
++        for
++        element
++        in
++        collection  # yup
++        if element is not None  # right
+     ]
+     lcomp2 = [
+         # hello
+@@ -123,7 +136,9 @@
+         # yup
+         for element in collection
+         # right
 -        if element is not None
--    ]
--    lcomp3 = [
--        # This one is actually too long to fit in a single line.
--        element.split("\n", 1)[0]
--        # yup
--        for element in collection.select_elements()
--        # right
++        if
++        element
++        is not None
+     ]
+     lcomp3 = [
+         # This one is actually too long to fit in a single line.
+@@ -131,7 +146,9 @@
+         # yup
+         for element in collection.select_elements()
+         # right
 -        if element is not None
--    ]
-+    lcomp = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+    lcomp2 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+    lcomp3 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
++        if
++        element
++        is not None
+     ]
      while True:
          if False:
-             continue
-@@ -143,7 +135,10 @@
+@@ -143,7 +160,10 @@
      # let's return
      return Node(
          syms.simple_stmt,
@@ -265,7 +272,7 @@ instruction()#comment with bad spacing
      )
  
  
-@@ -158,7 +153,11 @@
+@@ -158,7 +178,11 @@
  
  class Test:
      def _init_host(self, parsed) -> None:
@@ -407,9 +414,34 @@ short
         # yup
         arg3=True,
     )
-    lcomp = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-    lcomp2 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-    lcomp3 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+    lcomp = [
+        element  # yup
+        for
+        element
+        in
+        collection  # yup
+        if element is not None  # right
+    ]
+    lcomp2 = [
+        # hello
+        element
+        # yup
+        for element in collection
+        # right
+        if
+        element
+        is not None
+    ]
+    lcomp3 = [
+        # This one is actually too long to fit in a single line.
+        element.split("\n", 1)[0]
+        # yup
+        for element in collection.select_elements()
+        # right
+        if
+        element
+        is not None
+    ]
     while True:
         if False:
             continue

crates/ruff_python_formatter/tests/snapshots/black_compatibility@simple_cases__comments3.py.snap

@@ -60,22 +60,17 @@ def func():
 ```diff
 --- Black
 +++ Ruff
-@@ -6,14 +6,7 @@
-     x = """
-     a really long string
-     """
--    lcomp3 = [
--        # This one is actually too long to fit in a single line.
--        element.split("\n", 1)[0]
--        # yup
--        for element in collection.select_elements()
--        # right
+@@ -12,7 +12,9 @@
+         # yup
+         for element in collection.select_elements()
+         # right
 -        if element is not None
--    ]
-+    lcomp3 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
++        if
++        element
++        is not None
+     ]
      # Capture each of the exceptions in the MultiError along with each of their causes and contexts
      if isinstance(exc_value, MultiError):
-         embedded = []
 ```
 
 ## Ruff Output
@@ -89,7 +84,16 @@ def func():
     x = """
     a really long string
     """
-    lcomp3 = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+    lcomp3 = [
+        # This one is actually too long to fit in a single line.
+        element.split("\n", 1)[0]
+        # yup
+        for element in collection.select_elements()
+        # right
+        if
+        element
+        is not None
+    ]
     # Capture each of the exceptions in the MultiError along with each of their causes and contexts
     if isinstance(exc_value, MultiError):
         embedded = []

crates/ruff_python_formatter/tests/snapshots/black_compatibility@simple_cases__expression.py.snap

@@ -324,10 +324,14 @@ last_call()
 -{(i**2) for i in (1, 2, 3)}
 -{(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))}
 -{((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)}
--[i for i in (1, 2, 3)]
--[(i**2) for i in (1, 2, 3)]
--[(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))]
--[((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)]
++{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
++{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
++{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
++{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
+ [i for i in (1, 2, 3)]
+ [(i**2) for i in (1, 2, 3)]
+ [(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))]
+ [((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)]
 -{i: 0 for i in (1, 2, 3)}
 -{i: j for i, j in ((1, "a"), (2, "b"), (3, "c"))}
 -{a: b * 2 for a, b in dictionary.items()}
@@ -336,14 +340,6 @@ last_call()
 -    k: v
 -    for k, v in this_is_a_very_long_variable_which_will_cause_a_trailing_comma_which_breaks_the_comprehension
 -}
-+{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
-+{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
-+{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
-+{NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
-+[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
 +{NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
 +{NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
 +{NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
@@ -369,9 +365,6 @@ last_call()
 -    int,
 -    float,
 -    dict[str, int],
--]
--very_long_variable_name_filters: t.List[
--    t.Tuple[str, t.Union[str, t.List[t.Optional[str]]]],
 +    (
 +        str,
 +        int,
@@ -379,6 +372,9 @@ last_call()
 +        dict[str, int],
 +    )
  ]
+-very_long_variable_name_filters: t.List[
+-    t.Tuple[str, t.Union[str, t.List[t.Optional[str]]]],
+-]
 -xxxx_xxxxx_xxxx_xxx: Callable[..., List[SomeClass]] = classmethod(  # type: ignore
 -    sync(async_xxxx_xxx_xxxx_xxxxx_xxxx_xxx.__func__)
 -)
@@ -433,10 +429,11 @@ last_call()
  (*starred,)
  {
      "id": "1",
-@@ -208,24 +202,14 @@
+@@ -207,25 +201,15 @@
+ )
  what_is_up_with_those_new_coord_names = (coord_names | set(vars_to_create)) - set(
      vars_to_remove
- )
+-)
 -result = (
 -    session.query(models.Customer.id)
 -    .filter(
@@ -444,7 +441,7 @@ last_call()
 -    )
 -    .order_by(models.Customer.id.asc())
 -    .all()
--)
+ )
 -result = (
 -    session.query(models.Customer.id)
 -    .filter(
@@ -645,10 +642,10 @@ str or None if (1 if True else 2) else str or bytes or None
 {NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
 {NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
 {NOT_IMPLEMENTED_set_value for value in NOT_IMPLEMENTED_set}
-[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-[NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+[i for i in (1, 2, 3)]
+[(i**2) for i in (1, 2, 3)]
+[(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))]
+[((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)]
 {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
 {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
 {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}

crates/ruff_python_formatter/tests/snapshots/black_compatibility@simple_cases__power_op_spacing.py.snap

@@ -75,7 +75,7 @@ return np.divide(
 ```diff
 --- Black
 +++ Ruff
-@@ -15,38 +15,38 @@
+@@ -15,7 +15,7 @@
  b = 5 ** f()
  c = -(5**2)
  d = 5 ** f["hi"]
@@ -84,21 +84,16 @@ return np.divide(
  f = f() ** 5
  g = a.b**c.d
  h = 5 ** funcs.f()
- i = funcs.f() ** 5
- j = super().name ** 5
--k = [(2**idx, value) for idx, value in pairs]
-+k = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
- l = mod.weights_[0] == pytest.approx(0.95**100, abs=0.001)
+@@ -26,7 +26,7 @@
  m = [([2**63], [1, 2**63])]
  n = count <= 10**5
  o = settings(max_examples=10**6)
 -p = {(k, k**2): v**2 for k, v in pairs}
--q = [10**i for i in range(6)]
 +p = {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
-+q = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+ q = [10**i for i in range(6)]
  r = x**y
  
- a = 5.0**~4.0
+@@ -34,7 +34,7 @@
  b = 5.0 ** f()
  c = -(5.0**2.0)
  d = 5.0 ** f["hi"]
@@ -107,21 +102,15 @@ return np.divide(
  f = f() ** 5.0
  g = a.b**c.d
  h = 5.0 ** funcs.f()
- i = funcs.f() ** 5.0
- j = super().name ** 5.0
--k = [(2.0**idx, value) for idx, value in pairs]
-+k = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
- l = mod.weights_[0] == pytest.approx(0.95**100, abs=0.001)
+@@ -45,7 +45,7 @@
  m = [([2.0**63.0], [1.0, 2**63.0])]
  n = count <= 10**5.0
  o = settings(max_examples=10**6.0)
 -p = {(k, k**2): v**2.0 for k, v in pairs}
--q = [10.5**i for i in range(6)]
 +p = {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
-+q = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+ q = [10.5**i for i in range(6)]
  
  
- # WE SHOULD DEFINITELY NOT EAT THESE COMMENTS (https://github.com/psf/black/issues/2873)
 @@ -55,9 +55,11 @@
          view.variance,  # type: ignore[union-attr]
          view.sum_of_weights,  # type: ignore[union-attr]
@@ -164,13 +153,13 @@ g = a.b**c.d
 h = 5 ** funcs.f()
 i = funcs.f() ** 5
 j = super().name ** 5
-k = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+k = [(2**idx, value) for idx, value in pairs]
 l = mod.weights_[0] == pytest.approx(0.95**100, abs=0.001)
 m = [([2**63], [1, 2**63])]
 n = count <= 10**5
 o = settings(max_examples=10**6)
 p = {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
-q = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+q = [10**i for i in range(6)]
 r = x**y
 
 a = 5.0**~4.0
@@ -183,13 +172,13 @@ g = a.b**c.d
 h = 5.0 ** funcs.f()
 i = funcs.f() ** 5.0
 j = super().name ** 5.0
-k = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+k = [(2.0**idx, value) for idx, value in pairs]
 l = mod.weights_[0] == pytest.approx(0.95**100, abs=0.001)
 m = [([2.0**63.0], [1.0, 2**63.0])]
 n = count <= 10**5.0
 o = settings(max_examples=10**6.0)
 p = {NOT_IMPLEMENTED_dict_key: NOT_IMPLEMENTED_dict_value for key, value in NOT_IMPLEMENTED_dict}
-q = [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
+q = [10.5**i for i in range(6)]
 
 
 # WE SHOULD DEFINITELY NOT EAT THESE COMMENTS (https://github.com/psf/black/issues/2873)

crates/ruff_python_formatter/tests/snapshots/black_compatibility@simple_cases__slices.py.snap

@@ -43,7 +43,7 @@ ham[lower + offset : upper + offset]
 ```diff
 --- Black
 +++ Ruff
-@@ -4,28 +4,34 @@
+@@ -4,19 +4,21 @@
  slice[d::d]
  slice[0]
  slice[-1]
@@ -68,19 +68,11 @@ ham[lower + offset : upper + offset]
 +slice[
 +    (NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []) : x
 +]
-+slice[
-+     :: [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-+]
++slice[ :: [i for i in range(42)]]
  
  
  async def f():
--    slice[await x : [i async for i in arange(42)] : 42]
-+    slice[
-+        await x : [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []] : 42
-+    ]
- 
- 
- # These are from PEP-8:
+@@ -27,5 +29,5 @@
  ham[1:9], ham[1:9:3], ham[:9:3], ham[1::3], ham[1:9:]
  ham[lower:upper], ham[lower:upper:], ham[lower::step]
  # ham[lower+offset : upper+offset]
@@ -112,15 +104,11 @@ slice[not so_simple : 1 < val <= 10]
 slice[
     (NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []) : x
 ]
-slice[
-     :: [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-]
+slice[ :: [i for i in range(42)]]
 
 
 async def f():
-    slice[
-        await x : [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []] : 42
-    ]
+    slice[await x : [i async for i in arange(42)] : 42]
 
 
 # These are from PEP-8:

crates/ruff_python_formatter/tests/snapshots/format@expression__binary.py.snap

@@ -277,10 +277,10 @@ aaaaaaaaaaaaaa + {
     dddddddddddddddd,
     eeeeeee,
 }
-(
-    aaaaaaaaaaaaaa
-    + [NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in []]
-)
+aaaaaaaaaaaaaa + [
+    a
+    for x in bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
+]
 (
     aaaaaaaaaaaaaa
     + (NOT_YET_IMPLEMENTED_generator_key for NOT_YET_IMPLEMENTED_generator_key in [])

crates/ruff_python_formatter/tests/snapshots/format@statement__list_comp.py.snap

@@ -0,0 +1,86 @@
+---
+source: crates/ruff_python_formatter/tests/fixtures.rs
+input_file: crates/ruff_python_formatter/resources/test/fixtures/ruff/statement/list_comp.py
+---
+## Input
+```py
+[i for i in []]
+
+[i for i in [1,]]
+
+[
+    a  # a
+    for # for
+    c  # c
+    in  # in
+    e  # e
+]
+
+[
+    # above a
+    a  # a
+    # above for
+    for # for
+    # above c
+    c  # c
+    # above in
+    in  # in
+    # above e
+    e  # e
+    # above if
+    if  # if
+    # above f
+    f  # f
+    # above if2
+    if  # if2
+    # above g
+    g  # g
+]
+```
+
+## Output
+```py
+[i for i in []]
+
+[
+    i
+    for
+    i
+    in
+    [
+        1,
+    ]
+]
+
+[
+    a  # a
+    for  # for
+    c  # c
+    in  # in
+    e  # e
+]
+
+[
+    # above a
+    a  # a
+    # above for
+    for  # for
+    # above c
+    c  # c
+    # above in
+    in  # in
+    # above e
+    e  # e
+    # above if
+    if  # if
+    # above f
+    f  # f
+    # above if2
+    if  # if2
+    # above g
+    g  # g
+]
+```
+
+
+